This invention relates to loudspeaker devices having an improved low acoustic response characteristic.
In general, well known in the art as means of improving the low acoustic compass characteristics of a loudspeaker device are a bass reflex system in which a duct is formed on the baffle board of an enclosure, or a cabinet, and the low acoustic compass is intensified by the utilization of the resonance of the duct due to the back pressure of the loudspeaker unit, and a passive radiator system in which a diaphragm having a driving source is employed instead of the duct in the bass reflex system, the diaphragm being in resonance by the back pressure of the above-described loudspeaker unit so as to be operate as a passive radiator.
In either of these systems, the resonance operation is effective within a limited frequence range. Therefore, it is impossible to sufficiently increase the frequence range. In addition, since the resonance characteristics of these systems are different, it is difficult for these systems to provide desired reproduction characteristics.